With rapid development of the Internet, humans can easily access or distribute multimedia data across networks. Copyright security and protection of the data are becoming important issues. Digital watermarking has been proposed as a technology to ensure multimedia copyright protection. The technology uses a kind of marker to embed visually imperceptible yet electronically detectable signals or information into digital multimedia content, such as images, audios, and videos.
New methods and apparatus that assist in advancing technological needs and industrial applications in watermarking and digital watermarks are desirable.